With the improvements in the survival of low birth weight (LBW) infants there are compelling needs to enhance the quality of their life and shorten hospitalization time. Improved strategies for enteral nutritional support will optimize developmental outcome and shorten hospitalization through early independent oral feeding. Critical data are needed for the evaluation of the most appropriate time at which to begin enteral feedings (early vs late feeding), the type of feeding regimen (intermittent bolus vs continuous infusion), and when to introduce oral feeding. The effectiveness of feeding strategies depends upon the proper maturation of the infant's physiological functions. The hypotheses advanced in this application are: 1) that specific tube-feeding strategies differentially affect the maturation of physiological indices and the time of attainment of independent oral feeding; and 2) that relationships exist among physiological indices which influence the responses of the infant to a feeding strategy. This application will evaluate the following 2 specific aims: 1) To determine the effects of 4 tube-feeding strategies (early-onset intermittent bolus, early-onset continuous infusion, late-onset intermittent bolus, and late-onset continuous infusion) on the maturation of physiological indices: nutrition/metabolism (growth, mineral balance, bone mineralization, biochemical and hormonal responses), GI function (absorption, motility, permeability), and oral-motor kinetics (feeding proficiency, stress-related effects) as well as on the time at which the infant attains independent oral feeding; 2) To test the relationship between the attainment of independent oral feeding and the above physiological indices. Eighty LBW infants, 26 to 29 weeks gestation, stratified by gestational age, will be assigned to one of four treatments in a balanced two-way design where the two factors are time of initiation of feeding (early-onset vs late-onset) and the method of feeding (intermittent bolus vs continuous infusion). The results from this prospective, carefully controlled interdisciplinary study of infant feeding will provide practical information for caretakers of LBW infants as well as insight into the mechanisms by which feeding strategy affects the maturation of the LBW infant.